ATLAS reach for Quarkonium cross section and polarization measurement

TL;DR

This paper discusses the ATLAS detector's potential to measure Quarkonium production and polarization at the LHC using simulated data, focusing on early data analysis strategies and expected results.

Contribution

It presents a detailed analysis plan for Quarkonium measurements at ATLAS, including production mechanisms, polarization, and decay channels, based on simulated early LHC data.

Findings

Feasible measurement of Quarkonium cross sections and polarization at 14 TeV.

Strategies for separating prompt signals from backgrounds.

Expected ranges of transverse momentum and pseudorapidity for detection.

Abstract

The ATLAS detector at CERN's LHC is preparing to take data from the first proton-proton collisions expected in the next few months. We report on the analysis of simulated data samples for production of heavy Quarkonium states J/psi and Upsilon, corresponding to an integrated luminosity of 10 pb^-1 with center of mass energy of 14 TeV expected at the early ATLAS data. We review various aspects of prompt Quarkonium production at LHC: the accessible ranges in transverse momentum and pseudorapidity, spin alignment of vector states, separation of color octet and color singlet production mechanism and feasibility of observing radiative decays Xi_c and Xi_b decays. Strategies of various measurements are outlined and methods of separating promptly produced J/psi and Upsilon mesons from various backgrounds are discussed.